Mite Bites Tied To Cicada Emergence Causing Itchy Rash For Some In IL

ILLINOIS — It’s been months since billions of cicadas rose from the ground this spring to unleash their deafening mating calls, but their impact is still being felt in the Chicago area.

Dermatologists in the suburbs have seen a spike in patients with mite bites in recent weeks, Dr. Amy Derick, president of the Illinois Dermatological Society, told The Daily Herald, noting the bites appear to align geographically with cicada populations.

A similar situation occurred in 2007, when Brood XIII cicadas last surfaced in the state, according to the Illinois Natural History Survey. The mite Pyemotes herfsi, also known as the oak leaf itch mite, parasitized cicada eggs laid earlier that year in trees, resulting in an outbreak of bite rashes in August and September across Cook and DuPage Counties, according to the survey.

“It appears that this abundance of cicada eggs served as the host upon which populations of P. herfsi mites amplified to outbreak levels,” the survey said.

The same thing looks to be happening this time around, after Brood XIII and Brood XIX both surfaced in the area, the first time the two broods have overlapped since 1803.

“… because of the cicadas, they have a food source (and) their population has exploded,” Jennifer Rydzewski, of the Forest Preserve District of DuPage County, told the Herald of the mites.

While nearly invisible, the mites can bite, causing a red itchy rash with small raised bumps, according to PennState Extension, which noted it is only when they become very numerous and eliminate other food that the mites bite humans.

Up to 370,000 mites can fall daily from trees, according to the extension, which noted most bites happen while people are gardening, especially raking infested pin oak leaves.

Tree sprays are ineffective and DEET has yielded mixed results, so the best form of protection is to limit time under infested trees, immediately remove and wash clothing after possible exposure, and shower, according to the extension. Itch relief lotions and creams can help ease bite symptoms.